I would say this is fairly natural in small doses...I had an incredibly humiliating breakup with someone just over two years ago now, and I still feel that burning embarrassment that I let someone treat me like that whenever I think about it. It also makes me feel incredibly angry that someone could be so arrogant, condescending, patronising and hurtful. Rar. So yes sometimes I do wish he could see me now - more confident, far happier and with a boyfriend a hundred million times better. I also would be lying if I said I don't get a kind of smug pleasure knowing he hasn't slept with anyone since or even had any kind of real relationship with a girl. It just brings home the fact that I was a complete doormat and he hasn't managed to find anyone else to put up with him like I did. But I would say that if these thoughts are getting to the point where you are worried about your anger or your ability to let go, or if it's interfering with any other aspects of your life, you should perhaps talk to someone about resentment and moving on in life? Just a thought really.